My son’s name is Charlie. But lately I’ve come to think of him as The Gaping Maw.

At 14, Charlie’s 5-foot-8, having grown about two inches in each of the past five years. Many mornings he comes down to breakfast looking taller than he’d been the night before. And although he has plenty of interests, his primary activity lately seems to be scavenging for food.

Like many of us, when he gets hungry, he gets grumpy. So, to avoid that unpleasantness, and to fuel his physical growth, I try to keep him amply fed. But I’ve found that, in the effort to keep him full, my normal nutrition standards often fall by the wayside. Plus, I’m going broke!

At Charlie’s last checkup, the pediatrician told me that as long as Charlie’s healthy and physically active (as, thankfully, he is), I shouldn’t sweat the details of his diet too much.

Still, I’d like to do my best by him. So I asked some experts for tips on filling The Gaping Maw — without spending a fortune.

Hungry teenage boy waiting for food to be served (BigStock/BIGSTOCK)

Sarah Krieger, a spokeswoman for the American Dietetic Association, says my pediatrician’s advice is sound. “The key is to keep saturated fat to a minimum,” she says. “But if his cholesterol, weight and blood pressure are all within normal limits, he can afford” some flexibility in his diet.

Georgia Orcutt, author of the 2007 book “How to Feed a Teenage Boy” (Celestial Arts/Ten Speed Press), knows what I’m up against, having raised two boys herself. “I was just as overwhelmed as you are” when they were entering teendom, she says. Here’s her advice, based on her experience:

Jettison junk food. Orcutt believes it’s “critically important” for parents to help their children and teens develop healthful eating habits, which set the stage for good health through adulthood. She talked with her sons about what she calls the “political” aspect of making food choices. “Your dollar is a vote,” she told them, explaining that she was “not going to vote for those foods” by buying junk. “They got it right away,” she says, and began making their own healthful choices with their allowances.

Make it easy. Orcutt, a working mom, left two boxes (one for each boy) full of “healthy stuff” (baby carrots, sandwich fixings, mozzarella cheese sticks) in the fridge from which the kids could assemble snacks after school. “They knew there was food to eat,” she says, and that they could feed themselves by “just pulling this stuff out and eating it.”

Cook extra. Orcutt says she began cooking a lot more than she needed of such staples as rice (she mixed highly nutritious brown rice with less-nutritious white to make it more palatable), freezing portions in bags the boys could toss in the microwave. Other “extras” included roast chicken, grilled chicken breasts and ratatouille. And Orcutt made stews and soup — “a great food for kids,” she says. “They can’t eat it very fast, and they want to have it at the table and talk.”

Make mealtime flexible. “My kids wanted to eat a lot of meals, not just one huge meal, and not just three meals a day,” Orcutt says. “I love the idea of a family dinner,” she says, and so although they all sat down at the table together to talk, they didn’t necessarily all eat at the same time.

Teach cooking skills. Teenage boys are capable of far more than microwaving food, Orcutt notes. She taught her boys “simple sauteing techniques,” which she says they use to this day. (They’re now 20 and 23.) Stir-frying some of that microwaved rice with peppers, celery and onion is easy, she says; the boys could add protein by adding a bit of cooked meat or by “dropping an egg in and tossing it around.” Wraps are also easy: “There isn’t a food known that can’t go in a wrap,” Orcutt says; she suggests a filling and nutritious mix of beans, shredded lettuce and other vegetables, and “a little shredded cheese.”

Suggest smoothies. Full of protein, smoothies made with yogurt and fresh or frozen fruit are more filling than you might think; you can add extra nutrition by including peanut butter or flax seed in the mix.

Keep it affordable. Keeping a teenage boy full can be expensive. But Orcutt knows lots of penny-saving tips:

·Buy frozen fruits and vegetables. “You can find really great deals, and the nutrients sometimes are better than in the foods sitting in the produce section.”

·Buy in bulk. Barley, brown rice, oats, nuts and many other staples are readily available in bulk, either in your grocery store or at club stores such as Costco.

·Ration the protein. “It’s a mistake to think that teens need large amount of protein,” Orcutt says. “A one-pound salmon serves four people in our family.” She suggests limiting portions, “not covering the plate.” And, she adds, a vegetarian meal once or twice a week is healthful and can cut costs.

·Pick low-cost foods. “Eggs make a terrific meal, and even if they go up to $3 a dozen, they’re still a really great deal,” Orcutt says. And popcorn, which costs pennies compared with potato chips, “is wonderful stuff,” Orcutt says. “It’s high in fiber, really good for you.”

What a teen boy should eat in a day

Dietitian Sarah Krieger says an active 14-year-old boy can easily require 2,800 to 4,000 calories per day. She suggests checking www.choosemyplate.gov/myplate/index.aspx for an interactive tool that tells how to allocate those calories. Here’s how Krieger says Charlie’s daily diet should look:

·10 or more servings of grains, at least half whole grains. This category includes breads, pasta, rice, corn (including popcorn) and oats.

·6 or more cups of fruits and vegetables. They contain fiber, lots of vitamins and minerals and few calories.

·3 or more cups of milk. Stick with 1 percent fat or less to avoid saturated fat.